Isolated Resonant Switched Capacitor Converter With Voltage Self-Balancing Ability

Abstract

This article proposes an isolated resonant switched capacitor converter (I-RSCC) for high-voltage applications. The dc capacitors’ voltages achieve self-balancing with the resonant switched capacitor units (RSCUs). The voltage stress of the switching devices is reduced. The isolated rectifier (IR) is used for galvanic isolation and energy transfer. The number of switching devices is reduced by multiplexing parts switching devices functions, which helps the compact design. In this article, the topology and operation principle of I-RSCC are introduced in detail. Then, the output characteristics of I-RSCC are analyzed, including the voltage balance operation, the energy transmission path, the voltage conversion ratio, and the output power. The design example of I-RSCC is also presented. Finally, a 10-kW prototype is built to verify the feasibility of the proposed I-RSCC topology. The results show that soft switching is realized, and the maximum operation efficiency is 96.5% and above 96% at the rated power.